Supported privileges with predefined permissions are:

Administrative Privileges:

portal:admin:viewUsers: grants the ability to view full member account information within organization.

portal:admin:updateUsers: grants the ability to update member account information within organization.

portal:admin:deleteUsers: grants the ability to delete member accounts within organization.

portal:admin:inviteUsers: grants the ability to invite members to organization. (This privilege is only applicable to ArcGIS Online.)

portal:admin:disableUsers: grants the ability to enable and disable member accounts within organization.

portal:admin:changeUserRoles: grants the ability to change the role a member is assigned within organization; however, it does not grant the ability to promote a member to, or demote a member from, the Administrator role. That privilege is reserved for the Administrator role alone.

portal:admin:manageLicenses: grants the ability to assign licenses to members of organization.

portal:admin:reassignUsers: grants the ability to assign all groups and content of a member to another within organization.

Groups

portal:admin:viewGroups: grants the ability to view all groups within organization.

portal:admin:updateGroups: grants the ability to update groups within organization.

portal:admin:deleteGroups: grants the ability to delete groups within organization.

portal:admin:reassignGroups: grants the ability to reassign groups to other members within organization.

portal:admin:assignToGroups: grants the ability to assign members to, and remove members from, groups within organization.

portal:admin:manageEnterpriseGroups: grants the ability to link group membership to an enterprise group. (This privilege is only applicable to Portal for ArcGIS.)

portal:admin:createUpdateCapableGroup: grants the ability to create and own groups with item update capabilities.

Content

portal:admin:viewItems: grants the ability to view all content within organization.

portal:admin:updateItems: grants the ability to update content within organization.

portal:admin:deleteItems: grants the ability to delete content within organization.

portal:admin:reassignItems: grants the ability to reassign content to other members within organization.

portal:admin:shareToGroup: grants the ability to share other member's content to groups the user belongs to.

portal:admin:shareToOrg: grants the ability to share other member's content to organization.

portal:admin:shareToPublic: grants the ability to share other member's content to all users of the portal.

ArcGIS Marketplace Subscriptions

marketplace:admin:purchase: grants the ability to request purchase information about apps and data in ArcGIS Marketplace. (This privilege is only applicable to ArcGIS Online.)

marketplace:admin:startTrial: grants the ability to start trial subscriptions in ArcGIS Marketplace. (This privilege is only applicable to ArcGIS Online.)

marketplace:admin:manage: grants the ability to create listings, list items and manage subscriptions in ArcGIS Marketplace. (This privilege is only applicable to ArcGIS Online.)